1. Technical Field
Embodiments of the present invention generally relate to light emitting diode (LED) illuminating devices, and particularly to an LED illuminating device with a high heat dissipating efficiency and a light engine of the LED illuminating device.
2. Description of Related Art
Presently, LEDs (light emitting diodes) are preferred for use in LED illuminating devices rather than CCFLs (cold cathode fluorescent lamps) due to a high brightness, a long lifespan, and a wide color range of the LED.
For an LED, eighty percents to ninety percents of the power consumed by the LED is converted into thermal energy, and only ten percents to twenty percents of the power consumed by the LED is converted into light. In addition, a plurality of LEDs are generally packaged in a single LED illuminating device in order to obtain a desirable illumination brightness. Therefore, heat dissipation of the LED illuminating device is a problem inhibiting the application of the LED illuminating device, which requires to be resolved.
For a high brightness LED illuminating device, a highly efficient heat dissipation device is necessary in order to timely and adequately remove the heat generated by the LED illuminating device. Otherwise, the brightness, lifespan, and reliability of the LED illuminating device will be seriously affected. Conventional heat dissipation devices, such as heat sinks, can no longer satisfy the heat dissipation requirement of the high brightness LED illuminating device.
In order to enhance heat dissipation efficiency, air moving devices such as cooling fans are employed in combination with heat sinks to dissipate the heat of the high brightness LED illuminating device. The cooling fan generates an airflow which flows through the metal fins of the heat sink, to thereby dissipate the heat of the high brightness LED illuminating device. This kind of thermal design is suitable for a majority of LED illuminating devices, but is not suitable for some LED illuminating devices which have a critical heat dissipation requirement. It is believed that the heat dissipation efficiency of the conventional heat dissipation devices can be further improved.